Stormsock Heavyweight Knee.Features:100% Waterproof knee length sock with dense resilient Merino terry cushioning throughout, ideal for outdoor activities where an increased amount of insulation is desired.Composition:Outside:95% nylon (polyamide), 5% elastane.Inside:63% merino wool, 27% polyester, 7.5% nylon (polyamide), 2.5% elastane.Membrane:100% PU.